Barrier layer functioned novel-structure ceramic converter materials and light emitting devices

A light emitting device comprising:

• a light-emitting structure configured to emit a primary light having a first peak wavelength;
• and
• a ceramic wavelength converter assembly configured to receive the primary light from the light-emitting structure, the ceramic wavelength converter assembly comprising:
• two first layers comprising an undoped host material, or a doped host material;
• two second layers comprising a barrier material and being disposed between the two first layers;
• and
• a third layer comprising a doped host material, or an undoped host material and being disposed between the two second layers,
• wherein the two first layers comprise the undoped host material when the third layer comprises the doped host material, or
• wherein the two first layers comprise the doped host material when the third layer comprises the undoped host material.